<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
    .container{
        width: 500px;
        /* height: 500px; */
        background-color: pink;
        /* overflow:hidden;
        clear:both; */
    }
    .container::after{
        content:"";
        display:block;
        clear:both;
    }
    .box{
        width: 100px;
        height: 100px;
        background-color: aqua;
        margin:5px;
        float:left;
    }
    .text{
        width:100px;
        height:100px;
        background-color: blue;
        clear:both;
    }
</style>
</head>
<body>
    <div class="container">
        <div class="box"></div>
        <div class="box"></div>
        <div class="box"></div>
    <div class="text"></div>
    </div>

</body>
</html>